Diocletian and Maximian retired to private life in 305 A.D. Diocletian hoped his political reorganization would spare the empire civil strife over succession. However, the reforms kept the peace for a little over a year. Constantine assumed the title Augustus angering rivals. Maxentius convinced a cohort to support his elevation to the same position. The rebellion brought Diocletian out of retirement and led to an untenable arraignment involving four Augusti.
Constantius and Galerius succeeded Diocletian and Maximian as Roman emperors. Galerius convinced Diocletian to approve the promotions of Severus and Maximinus to Caesar. This precluded Maximian’s son Maxentius and Constantius’ son Constantine from the rule of four. The new Caesars enjoyed successful careers, solid resumes, and direct ties to Galerius. Severus served with the Augustus while Maximinus was his nephew. Diocletian and Maximian retired to private villas, but remained in contact with their successors.
Maximian disliked the new political settlement. He felt Galerius held too much power and resented the slight to his son. Meanwhile, Constantius campaigned against the Picts in Britain, declared victory and moved to winter quarters. The emperor grew ill that winter and died. Constantius declared his son, Constantine, as his successor. This move angered both Galerius and Maxentius. Galerius feared Constantine’s power while Maxentius felt slighted once again. Constantine agreed to the title Caesar to placate Galerius and Severus became Augustus. Maxentius appealed to the army and convinced some to support his claim as senior emperor in the west. Maximian supported his son’s revolt while the other emperors moved to quash it.
Severus marched on Rome to punish the upstart. Maxentius bribed Severus’ legions while others deserted to the rebellion out of respect for Maximian. The rebel army captured Severus and held him hostage. Then, Galerius marched on Maxentius, but failed to defeat the insubordinate aristocrat. After Galerius’ retreat, Maxentius prepared Rome for another assault. While Maxentius consolidated Rome under his rule, his father traveled to parlay with Constantine. Maximian convinced Constantine to support Maxentius in return for the rank of Augustus. Constantine would marry Maximian’s daughter, Fausta, and receive the promotion. In return, Constantine would remain neutral militarily.
Maximian placated Constantine and solidified his son’s position. Then, just as quickly, the father undermined the son. Maximian attacked Maxentius publicly and even ripped his son’s toga off. The army refused to support the elder and Maximian left Italy with his tail between his legs. However, his actions increased instability within the empire.
In 308, Galerius begged Diocletian to help resolve the turmoil.
Diocletian’s personal authority ended the troubles temporarily. He forced Maximian back into retirement. Galerius remained Augustus with Licinius promoted to Augustus in the west. Constantine and Maximinus became Caesars. However, Constantine and Maximinus refused to accept nothing less than Augustus and were promoted. As a result, Rome had four Augustus. The situation would not hold especially with Maxentius’ thirst for power.
An upstart nobleman threw a tantrum over not receiving a promotion and set in motion events that eventually spun out of control. Maxentius wanted to rule, but was bypassed for the emperor’s friends and relatives. When death opened the door, he rebelled, embarrassed two emperors, and then insulted his father. The empire’s patriarch emerged from retirement to try and settle matters. Diocletian managed to keep the peace for a year.